Steering rack - Too much air blows

[dstig1]

OK, here's the issue. Steering rack blew a couple weeks back (driver's side rack seal). Find replacement rack at Autozone for $215 (Ford was another +$100). Replace rack. PITA, but managed to do it OK. Noticed vibration especially when turning right in parking lots (slow speed). I figured out that it was air in the line easily enough, so I figured it was one of two things (the ONLY two things I touched) - the PS fittings to the rack, or the PS cooler hoses as they were kinda hardened and cracking a bit. Today I chopped off an inch of the PS cooler hoses and reattached them (nice flexible section now), and tightened down the main PS lines to the rack. Still I have air. I have not tried Ford/Helm's bleeding procedure (only tried the one that came with the American Remanufacturing - AMI - rack where you turn the wheel lock-to-lock 40 times with engine off) as I am not currently set up to do the vacuum bleeding procedure they discuss, but I could be, if needed.

I get the feeling there is a fitting that is not quite tight allowing air in, but there is no fluid leak anywhere. I only touched the two fittings to the rack, and the hoses to the PS cooler, but they have all now been rechecked and reworked. I was afraid of overtorquing the fittings at first, but I gave them a good bit more today (they said 15 ft-lbs which ain't much, but what idiot puts a torque spec on a fitting that can only be turned with an open end wrench?!??!)

I am not unfamiliar with car work as I have done everything on this car from new (including a clutch), so I don't think I am too much of an idiot. The car is 12+ yrs old, so I am looking more for "keeping it going" and not "cranking it up" here.

Annoyed and looking for suggestions!?!?!?!



-Dave
'92 5spd, 138k, some mild mods

 

[Rockledge]

Lock-to-lock 40 times with the engine off? That's a new one to me. I think the engine should at least be cranking so the pump is pumping, no?

I like to bleed the steering system by jacking up the front end so both tires are off the ground, engine on and car in nuetral, making sure the rpms are about 1-2K or so, and then I turn the wheels lock-to-lock slowly but consistently, not holding the wheel at the stops, for a couple of minutes. Works well for me.

Even taking the car to a large parking lot and turning the wheel lock-to-lock while the car is moving and engine running (pretend your in slow motion on a test course with cones lined up ) seems a better way to purge the air out of the system, IMO.

 

[Mels]

(they said 15 ft-lbs which ain't much, but what idiot puts a torque spec on a fitting that can only be turned with an open end wrench?!??!)

Torque Adapter. Use it at a 90 deg angle to your torque wrench. If necessary, cut one end open flare nut wrench style. If you can't find torque adapters, a simple crows foot will also work. Again, make sure that it is at a 90 deg angle to your wrench.

 

[dstig1]

Yeah, the bleeding procedure didn't make a whole lot of sense to me either, but I figured it was worth a whirl. I also tried letting the engine run for a bit too, and turning lock to lock. The other thing I notice is that I don't seem to have the problem after the car has sat overnight, but then it appears more obvious after driving a bit. It has to be sucking air in somewhere.

What I'm gathering from your post (Rockledge) is that this system should practically bleed itself without too much effort, which I was expecting. Since it keeps acting up, I'm convinced that it is sucking in air from somewhere. Since I have gone back and re-tightened and reworked the only fittings that I touched, I'm pointing more and more towards a slightly defective seal in the rack. Leaky enough to let air in under internal vacuum, but not leaky enough to let fluid out.

Although it is lifetime guaranteed, I do not relish R&R'ing it again...though it should be easier the second time as nothing is rusted, and I now know the trricks and maneuvers.

Grrrr.

And BTW, I dropped the rear subframe bolts an inch or two, and I am guessing it helped access a lot (never tried it without dropping it so it is hard to compare).

Any other sage advice out there?

Thanks,
Dave
'92 5spd 138k, some mods

 

[dstig1]

Figured I should update this. Since my last note, the problem has "fixed itself". More accurately, I figure there was way more air in the system than I thought and it just took a long time to work it's way out. That plus the previously mentioned bleeding procedure is apparently bunk. There is still more of a dead-spot/lash on center than the OEM rack had, but the mild "surging" feel that I would get in long corners, that I have heard other mention, is gone with the new rack.

Thanks for the tips.

I do think it is time to replace the lower control arms as I am now starting to get a vibration again. That would pretty much cover the front suspension/steering - all new except for the swaybar links, and a couple random bushings.

-Dave

 

[sdpatt]

Yes, the air will work its way out of the system after a while. I have tried the purge methods with no immediate effects. Several days of normal driving, however, brought the system back to normal operation.

If you are feeling vibration, look for a dynamic imbalance. Get those wheels and tires balanced. If you have side-to-side lunging over seams in the concrete while changing lanes on the highway or other streets, check those lower control arms, upper strut mounts, strut rod bushings and wheel bearings. Loose bearings or bushings don't create a vibration. They can aggravate one, but it takes a dynamic imbalance to create a vibration.

 

[projectSHO89]

Here's my sage advice, learned the hard way (of course!).

Install an inline filter, otherwise that surging on long sweeping turns will be back very soon.

Steve

 

[dstig1]

Oh yeah, I know it needs balancing/aligning. But I also need new tires, and I have new lower control arms coming. Need to wait until I get the ctrl arms in a few days, replace those, then bring it in for tires & alignment. I've been checking the wheel temps after driving and noticing nothing hot on either front wheel, so I'm assuming (perhaps incorrectly) that bearings are OK, as well as calipers still moving freely (I've had a stuck rear caliper before - I know how hot the wheel will get - burn your hand easily). I think I have been noticing some side to side lunging on the freeway, but I haven't been sure if it is real or an artifact of the rack having so much play on center. in any case, I'll see what it's like after the new arms, tires and balance/alignment. When I think about it, there aren't any more suspension parts to repalce after that, other than swaybar bushings and links (new Konis and urethane bushings at 70k, upper strut bearings/bushings a year ago, all new steering recently)

Install an inline filter, otherwise that surging on long sweeping turns will be back very soon

Can you give any more details? Where to put it, what kind, where to find one, etc. I might not bother as I have probably no more than 2 or 3 years left on this car, but I'll think about it.

Thanks,
Dave
'92 5spd, 140k